In some cases, an ailment may affect a patient's activity level or range of activities by preventing the patient from being active. For example, chronic pain may cause a patient to avoid particular physical activities, or physical activity in general, where such activities increase the pain experienced by the patient. Other ailments that may affect patient activity include movement disorders and congestive heart failure. When a patient is inactive, he may be more likely to be recumbent, i.e., lying down, or sitting, and may change postures less frequently.
In some cases, these ailments are treated via a medical device, such as an implantable medical device (IMD). For example, patients may receive an implantable neurostimulator or drug delivery device to treat chronic pain or a movement disorder. Congestive heart failure may be treated by, for example, a cardiac pacemaker.